User talk:Ahmadkhan5544

July 2020
Hello, I'm DVdm. I wanted to let you know that I reverted one of your recent contributions —specifically this edit to Elastic collision—because it did not appear constructive. If you would like to experiment, please use the sandbox. If you have any questions, you can ask for assistance at the Help desk. Thanks. DVdm (talk) 10:12, 7 July 2020 (UTC)